I have some trouble with the main tank of my Acroduster Too, and would like to change it.
On the Spruce web site, 2 differents tanks are available:
Main inverted tank (P/N 05-01071) or Main tank (P/N 05-19800).

The part number 05-19800 is listed as a fuel tank for a SA300 Starduster while the part number 05-01071 is for a tank with floptube and float sender though I see they list as both for an Acroduster...Dave Baxter to the rescue!_________________
Tim Parker
Socorro, NM
SA300 N169TR, SA100(almost)

Francois I am not sure what to tell you. As Tim pointed out the ( P/N 05-19800 ) is not only for the Starduster Too and is a standard tank IE: non inverted , it is also larger and will not fit in the Acroduster Too. ( P/N 05-01071 ) listed is the inverted tank for the SA-750 Acroduster Too and according to the web site comes with a flop tube and float sender. The original tanks made by Starduster Corp for the Acroduster had a barrel gauge with a spiral float sender, it mounted on top of the tank next to and aft of the filler cap and was mechanical, but many tanks were custom built and could have a number of changes . The tank offered ( P/N 05-01071 )says it comes with a float sender , this tells me that it is electrical?. Francois when was your Acroduster built, who built it, and does it have a mechanical or electrical fuel gauge?. Furthermore does the inverted fuel flop tube pick up enter the tank from the back or from the front? Even if you order this tank from A/S it may not be the same as yours as they are custom built to your order by A/S subcontractors and to get what you want you need to talk to whoever is going to build it Dave_________________Dave Baxter
Starduster History

Actually, my Acroduster was built in 1990/1994. The tank was provided by STOLP, with a barel gauge (spiral float sender), exactly as Dave describes it.
I am not sure that the 2 tanks from A/S would fit. This tank is very similar to the drawings of the book "Building the Gold Duster" (page 163).

My problem is a fuel leak from the inverted vent during inverted flight. I guess there should be a crack on that vent (but not visible, inside the tank).
As I have remove the upper wings (because an eyebolt of the cabane broke down), I decided to replace the fuel tank.

Anyway, thanks again for your answers, very interesting, and I will try to get in touch with an A/S specialist subcontracor (if possible).

Merci à vous, as we say in France
François
Below, my Acroduster some years ago

My SA-750 does the same fuel leak from the vent. On my airplane, the vent runs down from the forward top of the tank to a low point on the right side of the airframe inside the sheet metal, and then back up to the cabane. While upright, a small amount of fuel makes its way into the vent line and sits at the low point, especially if I overfill the tank. When I flip the airplane over, I get a little shot of fuel out the vent, which you can actually smell in flight. I probably lose about a tablespoon of fuel every time I fly inverted. Took me a while to figure it out.

Francois BFALCON Could right, as your problem could be a venting issue as opposed to an internal broken vent. For the system to work properly requires that the pressure be the same on both vents. If they are not, the dominant one will force fuel out of the opposing one. The procedure for adjusting the vents goes something like this, the lower vent ( right side up ) should terminate below the firewall facing directly into the relative wind. The upper vent ( upside down vent ) should go up the RH cabane strut and terminate approximately 4" below the center section pointed up at a 45 Degree angle when the airplane is in level flight fuel should come out of this vent ( as the lower one should be the dominate one ) you then bend this vent down until the fuel stops at this point the vents should have equal pressures as BFALCON said you will see some minor fuel leakage from aerobatic maneuvers as the airplane goes through positive and negative attitudes Dave_________________Dave Baxter
Starduster History

I am in the process of building, and have the inverted fuel tank. As received, I noticed a hole in the line of one of the tank vents at the tank fitting on the pilots' right side (the hole is through the tube on the inside of the tank - looks like a burn-through from welding). If that line was made the 'top' vent, then all the fuel in the tank would drain out during extended inversion!. I intend to make that line the bottom vent, that should result in the loss of about 4cc per flip. If your tank looses excessive ammounts, you may also have a hole in the line fitting. Any way, the vent lines will loose some fuel on each inversion - just the nature of the way the vents work in that tank._________________Paul

Paul & Frarcois Please go to Cam Meeks www.acroduster.net then look for the October 1977 issue of Starduster Magazine page 7,8.and 9 also you might look at the July 1980 page 15 and the October 1991 page 14 of the following issues RE: fuel systems and venting. When we are talking about these vents we must be clear as to the correct reference IE: setting in the pilots seat facing foreword the RH vent line ( INVERTED ) viewed from the rear should go up the RH cabane strut and face into the wind at approximately 45 degrees. The line inside the tank should go from that fitting down through the floor of the main tank and terminate just above the floor of the sump this vent will vent the tank when the aircraft is inverted. The middle fitting should be plugged, unless you have a return line from a pressure carb and some fuel injection systems. The LH vent line ( RIGHT SIDE UP ) viewed from the rear should leave that fitting and go up just above the the upper surface of the tank before descending to below the firewall and face directly into relative wind. The line inside the tank should go up close to the top of the tank and at that point in the top of the arc there should be a vent hole from there the line should descend through the floor of the main tank and terminate at the top of the sump this line vents the top of the main tank as well as the sump. These vents if built to the drawings cannot be reversed. Dave_________________Dave Baxter
Starduster History